Kwang Roh Park

Provision of the multimedia service framework in the ubiquitous home network

The paper proposes a methodology to provide the multimedia service framework to provide an integrated multimedia service in the ubiquitous home network. To do so, we define the requirements of a home media server (HMS), and implement its functionalities as a gateway for establishing connections between the home and external networks. The proposed HMS pursues, not only the integration of home network middleware technologies that allow automatic control and information sharing with various consumer electronics (CEs) and A/V devices, but also intended to provide context based intelligences to the multimedia services for the ubiquitous home environment .

A power saving system based on energy-aware control elements in ubiquitous home network

In this paper, we propose the system reducing the power consumption based on the energy-aware control elements (ECE). ECE refers to the minimum unit module providing a service within the single system. For example, the home gateway system provides the visitor identification service. If it is the case, the main processor, the Ethernet module, the MPEG encoding module built-in camera, and etc. are needed. We classify the main ECE, the Ethernet ECE, the MPEG encoder ECE, and etc. The home gateway system provides the service like not only the visitor identification service but also Internet service, VoIP service, IPTV service and the home automation service. This kind of services can be independently carried out and be performed together with other devices. The home gateway system can save the power consumption by activating only ECE which it is necessary according to the performed service. Also, we suggest the method for saving the power consumption by controlling only ECE required based on the communication traffic. We implement the technology monitoring the communication traffic in the home gateway system through FPGA. This FPGA monitors the communication traffic and distinguishes between the user valid packet and invalid packet. The software embedded in FPGA notifies so that the high layer application can control required ECE according to the user valid packet. We show the marvelous effect for power saving through the ECE base power saving system implementation.

An Enhanced Multi-path Scheme for QoS Guarantee in Wireless Sensor Network

A sensor network consists of a large number of sensor nodes that are densely deployed. The large scale sensor network is generally used for applications such as target tracking and emergency response rather than common data. The applications have real-time requirements that sensed data must be exactly delivered to a destination node within a given time. In this paper, we propose a multi-path scheme, which utilizes the virtual grid, to meet the real-time requirements. In order to select one of multi-paths depending on the service differentiation, the proposed scheme uses several information such as the size and transfer period of sensed data. In addition to an existing path, the proposed algorithm dynamically selects an alternative path according to multi-path environments. Moreover, it assigns the shortest path to the sensed data with most strict time restriction. Therefore, our scheme can guarantee the transmission reliability since sensed data is transmitted two or more routes by using the dualized multi-path on the virtual grid. In this paper, we introduce some realistic scenarios and propose an analytical model. Then performance of the proposed scheme is evaluated by numerical analysis. Our results show that the proposed scheme significantly outperforms the SPEED and MMSPEED.

An Algorithm for Congestion Control and Routing based Context-Aware in Wireless Sensor Networks

A wireless sensor network consists of a large number of sensor nodes that are randomly deployed. This network is formed to perform the critical mission. The essential elements for the wireless sensor network are a source and sink. Source senses stimulus initiating a critical mission and transmits collected data to a sink. In the wireless network, the environment where a single sink and a large number of sources are deployed is considered in general. Sources may communicate with a sink connected to the Internet. In this paper, we consider the aforementioned environment with a sink connected to the Internet and propose an efficient algorithm for controlling the congestion between a sink and a gateway. Moreover, we propose a routing protocol based on a situation aware profile which is obtained from sensed data.